Open carry is legal in Virginia (de facto, because there are no state laws prohibiting it, and there's that "right to bear arms" thing in the state constitution). I open carry occasionally, and know others who do, so here's my take.
1. Open carry means the firearm is clearly visible (from multiple angles), and it's obvious to an observer that it's a firearm (a belt holster with flap should be gun-shaped). An IWB holster with no covering garment is considered open carry.
2. Let your gun get wet? Use a flap holster? I don't know, what do cops do? It's not generally a problem in VA, because...
3. VA is shall-issue concealed carry, so it's easy to get a permit. The only reason most people open carry is to eat in a restaurant that serves alcohol, where concealed is prohibited (for now) but open carry is legal. Basically you walk up to the restaurant, "unconceal" by taking off a jacket or whatever, and go inside. "Printing" is therefore not a legal hazard, but I still try not to print.
Some people worry about getting harrassed by cops or store managers, but from what I've heard from people who carry a lot, that's pretty rare. It probably helps if you look vaguely like a cop or a fed. (I don't, unless undercover DEA counts.
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